A new method is being tested that is supposedly more accurate at detecting marijuana in a driver’s system. How does it work?

With the new system, a police officer would take a sample from the offender’s mouth, using a cotton swab to collect saliva. The testing kit boasts 100 percent accuracy rate for detecting marijuana use.

The new testing process would also speed result collection. Currently, states must submit samples to a lab for testing. This new test is said to take only minutes, so results could be obtained at the scene of [...]